JPH0329475B2 - - Google Patents

Abstract

1. Apparatus for water purification and/or aeration by saturation of the raw water with pressurized gas and subsequently allowing it to depressurize in a floating vessel characterized in that upstream to the flotation vessel (3) there are provided in series a first injector pump (1), a feed pump (4) and a second injector pump (2), and that the product water outlet (35) of the flotation vessel (3) through a throttle valve (39) is connected with the driving medium inlet (11) of the first injector pump (1), the suction inlet of which being designed as a gas suction inlet and the outlet of which feeds the driving medium inlet (21) of the second injector pump (2), the suction inlet (23) of the latter being designed as a raw water inlet.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention provides a method for purifying and/or aerating water by saturating the water with a gas under pressure and subsequent expansion in a floating vessel. METHODS AND APPARATUS.

Foreign matter separation with less pronounced phase separation gradients places increasingly high demands on the quality of wastewater and drinking water. Hydraulic engineering often deals with the separation of undissolved suspended solids or oil droplets. Membrane systems for desalinating and purifying water can also work without problems if, in a preliminary stage, all substances that would impair the function of the membrane are separated out by a long filtration.

Therefore, there is a need for a reliable separation method with high space yield, high separation performance, simple operation method, and low operating cost.

A small amount of residual material, which is not many milligrams per liter, is separated using a gravel filter, followed by flocculation and destabilization using a gold dust filter or a refining filter. Flotation methods are gaining importance due to oil and solids content.
In this method, suspended solids are evacuated by means of fine bubbles. Bubbles are created by increasing pressure to dissolve air, followed by expansion under atmospheric pressure, or also by electrolysis of water. However, with the equipment required to date, the flotation method has been a relatively expensive separation method. This known separation method of expansion flotation is usually carried out as follows. That is, a portion of the purified water is expanded after saturation in an autoclave supplied with gas by a compressor or compressed gas bottle and mixed with the waste water. This method itself is relatively complicated and requires compressors and requires high investments for autoclaves that can withstand the correspondingly high pressures.

The object of the invention is, therefore, to create a method and device for expansion and flotation, which can be operated reasonably and requires only a small outlay without the use of autoclaves and compressors.

With this invention, water is no longer saturated with air in a pressure tank using a compressor, but the saturated water to be treated is supplied to the flotation vessel via two jet pumps connected one after the other. , the first jet pump receives a partial stream of at least partially treated water as a conveyance carrier and draws in the gas which serves for flotation via a suction connection, while the discharge part of the first jet pump receives via a booster pump the gas which is used for flotation. A second connected jet pump absorbs the untreated water via the suction connection and supplies it to the flotation vessel.

The device of this invention is characterized by the following points. That is, a first jet pump, a booster pump, and a second jet pump are connected in series on the upstream side of the floating container, and the product water outlet of the floating container is communicated with the transport carrier inlet of the first jet pump via a throttle valve. , the suction connection of the first jet pump is designed as a gas absorption pipe, the discharge port 12 of the first jet pump communicates with the booster pump, and the booster pump 4 communicates with the carrier inlet 21 of the second jet pump. , the suction connection of the second jet pump is designed as a raw water inlet pipe.

A more detailed explanation will be given based on figures showing examples.

The figure is a flow sheet of the floating device of this invention.

The illustrated flotation device includes a first jet pump 1;
It is composed of a second jet pump 2, a floating container 3, and a booster pump 4.

The floating container 3 is composed of an upper part 31 that is partially cylindrical and partially conical. Connected to the upper part 31 is a downwardly directed narrow cylindrical part 32 . A vertical tube 33 is inserted into the floating container 3 from below. Rough water RW containing gas bubbles to be purified is supplied to this vertical pipe via a connection 34 . In the lower part of the flotation vessel 3, purified water can be taken out at 35. A connecting portion 36 provided in the upper part of the floating container 3 allows the transported foreign matter S to be taken out with a pump.

Purified product water PW is taken out from the connection part 35 via a conduit 37. Via a branch line 38 and a flow distributor or throttle 39, a portion of the already treated water is sent to the carrier inlet 11 of the first jet pump 1. The suction chamber of the first jet pump 1 is introduced via a connection 13 with the gas required for flotation, in particular purified air L. This air L is sucked into the connecting portion 13 by the negative pressure of the first jet pump 1. The discharge part of the first jet pump 1, whose flow is maintained by a booster pump 4 placed between the first and second jet pumps 1 and 2, connects to the carrier injection port 21 of the second jet pump 2 via the booster pump 4. It's communicating. The suction chamber of the second jet pump 2 receives the raw water RW to be purified via the suction connection 23. The discharge part 22 of this second jet pump 2 is connected to an open connection part 34 of a vertical pipe 33. The pressure drop that occurs during expansion in the second jet pump 2 is due to the
Used for transporting RW. The crude water is mixed with the smallest air bubbles, which can then be separated in the flotation vessel 3. The insoluble water components that entered through the vertical pipe 33 and were mixed with small bubbles are transferred to the upper connection 36, as already mentioned, and the purified product water PW is transferred to the lower connection 35 of the floating vessel 3. It is taken out at the location.

The advantages of the flotation device according to the invention, compared to conventionally known inflatable flotation devices, are as follows. That is, there is no need for a compressor that is prone to failure and that produces noise, as well as a pressure vessel that has large walls for safety reasons. This is because the energy consumed on the suction side of the first jet pump 1 to generate pressure is transferred to the booster pump 4 and the second jet pump 2.
This is because it is partially regenerated by applying pressure between them. Thus, the first jet pump 1
The air sucked in is dissolved in the carrier and saturated.

The principle advantage of this method is that it is less expensive to manufacture and operate compared to traditional flotation devices and operates without solid separation materials, solving many problems in water engineering for separating turbid substances, oils or fats. It becomes easy to use for

When attempting to saturate a liquid with gas, the efficiency of introducing air into the fluid phase is generally low. Furthermore, the transport of gas from the bubbles is hindered by the surfactant. As such, in biological clarification devices with surface ventilation, the resuscitation air carrier reduction is only 1-2%.

In the apparatus according to the present invention, the two jet pumps connected one behind the other with the booster pump 4 interposed therebetween can effectively saturate the carrier with gas in the fluid. The liquid is now saturated with air, since the water flow pushed back during expansion no longer forms small bubbles behind the second jet pump. In this way, the pressure of the carrier is rapidly increased between the first and second jet pumps 1 and 2 with the booster pump 4 in between, so that gases such as air are well dissolved in the liquid carrier, and the gas is It becomes saturated in the liquid.

In view of the above, the configuration of the present invention in which two jet pumps are disposed in front and behind each other is particularly well suited for clarifiers in fishponds and the like. The water flow can be adjusted to separate an amount of dissolved air in the form of bubbles for solids removal.

[Brief explanation of the drawing]

The figure is a flow sheet of the flotation device. Codes in the figure: 1, 2...Jet pump, 3...
Floating container, 4... Booster pump, 11, 12...
...Transport carrier inlet, 12, 22...Discharge part, 1
3, 23...Suction connection part, 35...Product water outlet,
39... Throttle valve.

Claims (1)

[Claims] 1. A method for purifying water by saturating the water with a compressed gas and subsequently expanding it in the flotation vessel 3, comprising: The first jet pump 1, the booster pump 4, and the second jet pump 2 are connected in series in this order, and the first jet pump 1 is connected to the floating vessel 3.
The second jet pump 2 receives a partial stream of the water treated at the pump and absorbs the gas L which is useful for flotation via the suction connection 13, and the second jet pump 2 connects the suction connection 23 to supply the untreated water RW to the flotation vessel 3. A method characterized in that the untreated water RW is absorbed through the water. 2. A device for purifying water by saturating the water with a compressed gas and subsequently expanding it in a flotation vessel 3, in which a first jet pump 1 and a booster are provided upstream of the flotation vessel 3. a pump 4 and a second jet pump 2 are connected in series in this order, said first jet pump 1 receiving at least a partial flow of the treated water as a transport carrier from the product water outlet 35 of the flotation vessel 3 via a valve 39; The second jet pump 2 absorbs the gas L useful for flotation through the suction connection 13, and its discharge part 12 communicates with the booster pump 4. It communicates with the discharge part 12 of the first jet pump 1 through the pipe, and its suction connection part 23 is formed as an inflow pipe for the rough water RW, and its discharge part 12
is in communication with the flotation container 3. 3. In the device according to claim 2, the floating container 3 is formed in a conical shape and has a vertical pipe 33 extending from bottom to top, which pipe is connected to the discharge of the second jet pump 2. A device connected to the outlet 22, characterized in that the container is provided with a product water outlet 35 in a relatively narrow annular space 32 surrounding a vertical tube 33 in its lower part. 4. Device according to claim 2 or 3, characterized in that the flotation vessel 3 has an outlet 36 for the flushed material in the upper, dome-shaped part.